CVE-2023-20089 | Cisco Nexus 9000 Series Fabric Switches in ACI Mode Link Layer Discovery Protocol Memory Leak Denial of Service Vulnerability

A vulnerability in the Link Layer Discovery Protocol (LLDP) feature for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) Mode could allow an unauthenticated, adjacent attacker to cause a memory leak, which could result in an unexpected reload of the device. This vulnerability is due to incorrect error checking when parsing ingress LLDP packets. An attacker could exploit this vulnerability by sending a steady stream of crafted LLDP packets to an affected device. A successful exploit could allow the attacker to cause a memory leak, which could result in a denial of service (DoS) condition when the device unexpectedly reloads. Note: This vulnerability cannot be exploited by transit traffic through the device. The crafted LLDP packet must be targeted to a directly connected interface, and the attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent). In addition, the attack surface for this vulnerability can be reduced by disabling LLDP on interfaces where it is not required.

Published: 2023-02-23 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-20089 is rated Moderate Risk (51.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.42%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-20089

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-09 0.15% 0.42% +0.27%
2 2026-02-25 0.05% 0.15% +0.10%
3 2024-08-05 0.05%

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-20089

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.4 3.1 HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 4.0 [email protected]
6.5 3.1 MEDIUM
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 3.6 [email protected]

Weakness enumeration for CVE-2023-20089

Affected software / configurations for CVE-2023-20089

Vendor Product Version Raw CPE
cisco nx-os 15.2\(1g\) cpe:2.3:o:cisco:nx-os:15.2\(1g\):*:*:*:*:*:*:*
cisco nx-os 15.2\(2e\) cpe:2.3:o:cisco:nx-os:15.2\(2e\):*:*:*:*:*:*:*
cisco nx-os 15.2\(2f\) cpe:2.3:o:cisco:nx-os:15.2\(2f\):*:*:*:*:*:*:*
cisco nx-os 15.2\(2g\) cpe:2.3:o:cisco:nx-os:15.2\(2g\):*:*:*:*:*:*:*
cisco nx-os 15.2\(2h\) cpe:2.3:o:cisco:nx-os:15.2\(2h\):*:*:*:*:*:*:*
cisco nx-os 15.2\(3e\) cpe:2.3:o:cisco:nx-os:15.2\(3e\):*:*:*:*:*:*:*
cisco nx-os 15.2\(3f\) cpe:2.3:o:cisco:nx-os:15.2\(3f\):*:*:*:*:*:*:*
cisco nx-os 15.2\(3g\) cpe:2.3:o:cisco:nx-os:15.2\(3g\):*:*:*:*:*:*:*
cisco nx-os 15.2\(4d\) cpe:2.3:o:cisco:nx-os:15.2\(4d\):*:*:*:*:*:*:*
cisco nx-os 15.2\(4e\) cpe:2.3:o:cisco:nx-os:15.2\(4e\):*:*:*:*:*:*:*
cisco nx-os 15.2\(4f\) cpe:2.3:o:cisco:nx-os:15.2\(4f\):*:*:*:*:*:*:*
cisco nx-os 15.2\(5c\) cpe:2.3:o:cisco:nx-os:15.2\(5c\):*:*:*:*:*:*:*
cisco nx-os 15.2\(5d\) cpe:2.3:o:cisco:nx-os:15.2\(5d\):*:*:*:*:*:*:*
cisco nx-os 15.2\(5e\) cpe:2.3:o:cisco:nx-os:15.2\(5e\):*:*:*:*:*:*:*
cisco nx-os 16.0\(1g\) cpe:2.3:o:cisco:nx-os:16.0\(1g\):*:*:*:*:*:*:*
cisco nx-os 16.0\(1j\) cpe:2.3:o:cisco:nx-os:16.0\(1j\):*:*:*:*:*:*:*

References for CVE-2023-20089

cvelogic Threat Intelligence